TCA Cycle and Pyruvate Dehydrogenase Complex
50 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

During which week is the lecture on antibodies and their applications scheduled?

  • Week 3
  • Week 2 (correct)
  • Week 1
  • Week 4

Which day of the week does the BMOL20110 course have a lecture in the A-H2.18-SCH room?

  • Monday
  • Thursday
  • Wednesday
  • Friday (correct)

What is NOT covered in the first week of the BMOL20110 course?

  • The physical basis of life
  • Secondary structure of proteins
  • Diversity of protein functions
  • Molecular motors (correct)

What concept is introduced in the first lecture of the course?

<p>Biomolecular interactions (C)</p> Signup and view all the answers

Which topic is likely to include clinical analyses of protein dysfunction?

<p>Protein dysfunction and disease (A)</p> Signup and view all the answers

What is the scheduled time for lectures on Mondays in the first trimester?

<p>13:00-14:00 (D)</p> Signup and view all the answers

What is the primary catabolic purpose of the citric acid cycle?

<p>To oxidize acetyl CoA and produce electron carriers (B)</p> Signup and view all the answers

Why is the reaction catalyzed by the pyruvate dehydrogenase complex considered a crucial juncture in metabolism?

<p>It links glycolysis to the citric acid cycle (C)</p> Signup and view all the answers

How is the citric acid cycle primarily regulated?

<p>Through feedback inhibition by ATP and NADH (B)</p> Signup and view all the answers

What is the role of the electron carriers produced in the citric acid cycle?

<p>They facilitate oxidative phosphorylation in the mitochondria. (D)</p> Signup and view all the answers

What is the significance of oxidizing acetyl CoA in the citric acid cycle?

<p>It generates metabolic intermediates for biosynthesis. (D)</p> Signup and view all the answers

Which of the following best explains the efficiency of the citric acid cycle?

<p>It maximizes the yield of electron carriers per molecule of acetyl CoA. (B)</p> Signup and view all the answers

Which of the following statements about lipid metabolism and beta oxidation is most accurate?

<p>It converts lipids into acetyl CoA, which enters the citric acid cycle. (B)</p> Signup and view all the answers

Which aspect of amino acid metabolism is emphasized in the metabolism curriculum?

<p>They can be converted into intermediates that enter the citric acid cycle. (C)</p> Signup and view all the answers

What are the main steps involved in converting pyruvate to acetyl CoA?

<p>Decarboxylation, oxidation, and transfer of the acetyl group (B)</p> Signup and view all the answers

What role does Coenzyme A play in the conversion of pyruvate to acetyl CoA?

<p>It forms a high-energy bond with the acetyl group (C)</p> Signup and view all the answers

Which of the following molecules is produced in the process along with acetyl CoA?

<p>NADH (D)</p> Signup and view all the answers

What is the chemical structure that acetyl CoA carries?

<p>Acetyl group (C)</p> Signup and view all the answers

Which cofactor is essential for the decarboxylation step during the conversion of pyruvate to acetyl CoA?

<p>Thiamine pyrophosphate (TPP) (C)</p> Signup and view all the answers

Where does the conversion of pyruvate to acetyl CoA primarily take place in a cell?

<p>Mitochondrion (D)</p> Signup and view all the answers

What is the byproduct of pyruvate conversion in addition to acetyl CoA?

<p>Carbon dioxide (CO2) (A)</p> Signup and view all the answers

Which molecule is formed during the oxidation step of pyruvate conversion?

<p>NADH (B)</p> Signup and view all the answers

What is the primary function of the transport protein in the context of pyruvate conversion?

<p>Carrying acetyl CoA into the mitochondrion (B)</p> Signup and view all the answers

Which of the following correctly describes the final product of pyruvate conversion?

<p>It enters the citric acid cycle for energy production (D)</p> Signup and view all the answers

What is the primary outcome of hydrogen combining with oxygen in cellular respiration?

<p>Formation of water from hydrogen and oxygen (D)</p> Signup and view all the answers

Which of the following reflects a difference between cellular respiration and an explosive reaction involving hydrogen and oxygen?

<p>In cellular respiration, hydrogen is derived from organic molecules. (C)</p> Signup and view all the answers

During which process are electrons released as they move closer to electronegative oxygen atoms?

<p>Cellular respiration (C)</p> Signup and view all the answers

How does glycolysis facilitate the breakdown of glucose?

<p>Through a sequence of enzymatic reactions (B)</p> Signup and view all the answers

What role does NADH play in the process of cellular respiration?

<p>It captures energy from carbohydrates and transports it. (D)</p> Signup and view all the answers

What happens to the charge on the charged electrons when they enter the reaction with oxygen?

<p>They lose their charge and neutralize. (D)</p> Signup and view all the answers

Which statement accurately describes the nature of respiration compared to other reactions?

<p>It is a continuous process occurring in various cells. (B)</p> Signup and view all the answers

Which of the following is a critical reactant for the formation of water during cellular respiration?

<p>Hydrogen (C)</p> Signup and view all the answers

What is the role of activated carrier molecules like ATP and NADPH in cellular reactions?

<p>They catalyze the transfer of phosphate groups in reactions. (D)</p> Signup and view all the answers

What molecule is directly produced from glycolysis?

<p>Pyruvate (D)</p> Signup and view all the answers

During which step is NADH formed in cellular respiration?

<p>During pyruvate dehydrogenase reaction (C)</p> Signup and view all the answers

How are activated carriers typically generated?

<p>In reactions coupled to the hydrolysis of ATP. (B)</p> Signup and view all the answers

What additional groups can be transferred by activated carrier molecules apart from electrons?

<p>Methyl, carboxyl, and glucose groups. (D)</p> Signup and view all the answers

What major metabolic pathway involves both NADH and acetyl CoA?

<p>Krebs cycle (B)</p> Signup and view all the answers

What is the specific energy role of NADPH in cellular processes?

<p>It transfers electrons and hydrogens during biosynthetic reactions. (A)</p> Signup and view all the answers

What is the ultimate purpose of the reactions coupled to ATP hydrolysis?

<p>To drive the formation of activated carriers for biosynthesis. (D)</p> Signup and view all the answers

What is produced during the conversion of pyruvate to acetyl CoA?

<p>NADH and CO2 (B)</p> Signup and view all the answers

Which cycle is also known as the tricarboxylic acid cycle?

<p>Citric acid cycle (A)</p> Signup and view all the answers

What role do NAD+ and FAD play in the citric acid cycle?

<p>They act as electron carriers. (A)</p> Signup and view all the answers

What is the initial reactant that enters the citric acid cycle?

<p>Acetyl CoA (A)</p> Signup and view all the answers

How many molecules of CO2 are released during one turn of the citric acid cycle?

<p>Two (C)</p> Signup and view all the answers

What process generates ATP in the citric acid cycle?

<p>Substrate-level phosphorylation (B)</p> Signup and view all the answers

Which of the following best describes the role of Coenzyme A in metabolism?

<p>It helps in the transfer of acetyl groups. (A)</p> Signup and view all the answers

What is a key result of glycolysis that is further processed in the citric acid cycle?

<p>Pyruvate (C)</p> Signup and view all the answers

What type of reaction occurs when electrons are transferred from NAD+ to other molecules in the citric acid cycle?

<p>Oxidation (D)</p> Signup and view all the answers

How many NADH molecules are produced during one turn of the citric acid cycle?

<p>Three (A)</p> Signup and view all the answers

Flashcards

Lecture 24

A lecture on the TCA Cycle in Biomolecular Sciences

TCA Cycle

A metabolic cycle that plays a key role in energy production in cells

Biomolecular Sciences

Branch of science dealing with biological molecules and their interactions.

Metabolic Pathway

Series of interconnected chemical reactions in a cell involving the transfer and transformation of energy and matter.

Signup and view all the flashcards

Key Metabolic Pathways

Essential biochemical routes crucial for energy generation and cellular functions.

Signup and view all the flashcards

BMOL20110

Course code for Biomolecular Sciences module.

Signup and view all the flashcards

Module Co-ordinator

Professor responsible for the course BMOL20110.

Signup and view all the flashcards

Lecture Schedule

Course lecture dates, days, and times.

Signup and view all the flashcards

Glycolysis

The process of breaking down glucose into smaller molecules.

Signup and view all the flashcards

Cellular Respiration

The process of releasing energy from organic molecules by reacting them with oxygen.

Signup and view all the flashcards

Electron Transport Chain

A series of protein complexes that transfer electrons to create energy.

Signup and view all the flashcards

Hydrogen Reaction with Oxygen

A reaction releasing energy as electrons move closer to oxygen.

Signup and view all the flashcards

Organic Molecules

Molecules containing carbon.

Signup and view all the flashcards

NADH

A molecule used to carry high-energy electrons in respiration.

Signup and view all the flashcards

Enzyme

Protein that speeds up chemical reactions.

Signup and view all the flashcards

Stepwise Energy Harvest

Energy released in respiration by taking small steps.

Signup and view all the flashcards

Pyruvate Dehydrogenase Complex

A crucial enzyme complex in metabolism responsible for converting pyruvate into acetyl CoA.

Signup and view all the flashcards

Citric Acid Cycle's Catabolic Purpose

The cycle oxidizes acetyl CoA to produce energy in the form of ATP and reducing power (NADH and FADH2).

Signup and view all the flashcards

Citric Acid Cycle's Efficiency

Efficiently oxidizing acetyl CoA to extract energy, with high energy yield from reducing equivalents.

Signup and view all the flashcards

Citric Acid Cycle Regulation

The cycle's rate is controlled to meet the cell's energy needs by feedback mechanisms and energy charges.

Signup and view all the flashcards

Lipid Metabolism

Metabolic pathways responsible for the breakdown, synthesis, and regulation of lipids.

Signup and view all the flashcards

Oxidative Phosphorylation

The process of generating ATP from the energy released by the electron transport chain.

Signup and view all the flashcards

Amino Acid Metabolism

Metabolic pathways responsible for the breakdown, synthesis, and regulation of amino acids.

Signup and view all the flashcards

Activated Carrier

A molecule that carries and transfers specific chemical groups, like phosphate, electrons, or methyl groups, to other molecules, facilitating reactions.

Signup and view all the flashcards

ATP (Adenosine Triphosphate)

A key energy carrier molecule in cells, used to drive various cellular processes. It transfers phosphate groups to other molecules, releasing energy.

Signup and view all the flashcards

NADPH (Nicotinamide Adenine Dinucleotide Phosphate)

An activated carrier involved in transferring electrons and hydrogen ions. It plays a vital role in anabolic reactions, such as photosynthesis.

Signup and view all the flashcards

Pyruvate

A three-carbon molecule that is a product of glycolysis, the breakdown of glucose, and a key intermediate for further energy production.

Signup and view all the flashcards

Acetyl-CoA

An activated carrier that carries acetyl groups, crucial for energy production in the citric acid cycle (TCA cycle) and biosynthesis.

Signup and view all the flashcards

TCA Cycle (Citric Acid Cycle)

A cyclic metabolic pathway in which acetyl-CoA is oxidized, generating energy, and reducing power in the form of ATP, NADH, and FADH2

Signup and view all the flashcards

Decarboxylation

A chemical reaction where a carboxyl group (COOH) is removed from a molecule, often releasing carbon dioxide as a byproduct.

Signup and view all the flashcards

Pyruvate Decarboxylation

The first step in converting pyruvate to acetyl CoA, where a carbon dioxide molecule is removed from pyruvate.

Signup and view all the flashcards

Pyruvate Oxidation

The second step in converting pyruvate to acetyl CoA, where pyruvate is oxidized, losing electrons and becoming a more reactive compound.

Signup and view all the flashcards

Acetyl Group Transfer

The final step in converting pyruvate to acetyl CoA, where the resulting two-carbon fragment is attached to Coenzyme A.

Signup and view all the flashcards

Coenzyme A (CoA)

A carrier molecule essential for many metabolic reactions, particularly in the transfer of acyl groups.

Signup and view all the flashcards

Mitochondrion

An organelle found in eukaryotic cells, responsible for generating ATP through cellular respiration.

Signup and view all the flashcards

Lipoic Acid

A cofactor involved in the TCA cycle, facilitating electron transfer during oxidation reactions.

Signup and view all the flashcards

Thiamine Pyrophosphate (TPP)

An important coenzyme involved in the decarboxylation of pyruvate, facilitating the removal of a carbon dioxide molecule.

Signup and view all the flashcards

Citric Acid Cycle

A series of chemical reactions in the mitochondria that breaks down acetyl CoA to generate energy in the form of ATP, NADH, and FADH2.

Signup and view all the flashcards

Krebs Cycle

A third name for the citric acid cycle, named after its discoverer, Hans Krebs.

Signup and view all the flashcards

Electron Transfer in the TCA Cycle

During the cycle, electrons are transferred from NAD+ to NADH and from FAD to FADH2. These electron carriers store energy that is later used to produce ATP.

Signup and view all the flashcards

ATP Production in the TCA Cycle

The citric acid cycle directly produces a small amount of ATP but primarily generates electron carriers (NADH and FADH2) whose energy is used for ATP synthesis in oxidative phosphorylation later.

Signup and view all the flashcards

Role of Coenzyme A

Coenzyme A is a vital molecule in the breakdown of carbohydrates and fats. It acts as a carrier for acetyl groups, transporting them to the citric acid cycle for energy generation.

Signup and view all the flashcards

Study Notes

TCA Cycle Lecture Notes

  • The TCA cycle, also known as the citric acid cycle or Krebs cycle, is a crucial metabolic pathway.
  • It's a central part of cellular respiration, oxidizing acetyl CoA to carbon dioxide.
  • This process releases energy stored in the chemical bonds of glucose, utilizing that energy to form ATP.
  • The cycle begins with the combination of acetyl CoA with oxaloacetate, forming citrate.
  • The cycle continuously works in a cyclical manner.
  • A series of reactions converts citrate, ultimately regenerating oxaloacetate, which allows the cycle to begin again.

Pyruvate Dehydrogenase Complex

  • The enzyme complex catalyzes the conversion of pyruvate to acetyl CoA.
  • This is a crucial step, linking glycolysis and the TCA cycle.
  • The conversion of pyruvate to acetyl CoA is irreversible.
  • The complex is regulated by the amounts of ATP, CoA, NADH, and ADP.

Regulation of the Citric Acid Cycle

  • The cycle's rate is adjusted to meet ATP demand.
  • Control points include isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase.
  • These enzymes are sensitive to the concentrations of ATP and NADH.

Important Molecules in the Cycle

  • Citrate, isocitrate, α-ketoglutarate, succinyl-CoA, succinate, fumarate, and malate are key intermediates in the cycle.
  • NAD+ and FAD act as electron carriers reducing to NADH and FADH2.
  • Coenzyme A (CoA) is a crucial coenzyme.
  • These molecules are vital for the flow of the cycle.

Summary of the TCA Cycle

  • The TCA cycle is a central metabolic pathway for the oxidation of acetyl CoA.
  • Oxidized carbon atoms in acetyl CoA are released as CO2.
  • The cycle produces high-energy molecules like NADH and FADH2, which deliver electrons to the electron transport chain.
  • The cycle plays a critical role generating ATP (adenosine triphosphate), the cell’s primary energy currency.

Energy Production

  • The electron carriers, NADH and FADH2, carry energy to the electron transport chain.
  • This process generates a large amount of ATP through oxidative phosphorylation.
  • Each NADH yields approximately 2.5 ATP, and each FADH2 roughly 1.5 ATP.
  • This is a significant energy source for the cell’s work.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Lecture 3. TCA Cycle_JR - Biomolecular Sciences Lecture Notes PDF

Description

Explore the essential components of the TCA cycle, also known as the citric acid cycle or Krebs cycle, and its role in cellular respiration. Understand the conversion of pyruvate to acetyl CoA and how these processes are regulated to meet ATP demands.

More Like This

Cellular Respiration and TCA Cycle
32 questions

Cellular Respiration and TCA Cycle

StableEpilogue avatar
StableEpilogue
TCA
44 questions

TCA

ImpeccableImagery avatar
ImpeccableImagery
TCA Cycle Overview and Glycolysis
9 questions

TCA Cycle Overview and Glycolysis

CohesiveRetinalite8453 avatar
CohesiveRetinalite8453
Biochemistry Chapter: TCA Cycle and Link Reaction
21 questions

Biochemistry Chapter: TCA Cycle and Link Reaction

AppropriateJasmine5753 avatar
AppropriateJasmine5753
Use Quizgecko on...
Browser
Open
Browser
Browser